I wouldn't have thought so. It's works on a "give this student 3 (say) pieces of work to mark (if possible) NOW!" basis when the student goes into the workshop. Once those pieces of work have been allocated they stay allocated (for reasons explained above). There is obviously no way of knowing the order in which the students will visit the workshop. When the Overallocation level is zero, I think the potential for gumming up is always present because there is a possibility that the work from the last one or two students to visit the workshop might be amongst the remaining pieces of unallocated work. It's unlikely but nevertheless a real possibility. In that case the students would be allocated 2 pieces rather than 3 to mark. That would be avoided if the overallocation level is set to 1. Our "last students standing" would then end up with 3 pieces of work and one or two of the submissions would be marked 4 times and their work only twice.
A job for Better Algorithms 'R' Us then. Possibly but I suspect there will always be a degree of unbalance as not all the students will do their full allocation of assessments for all sorts of good and not so good reasons. The current algorithm is robust and it works OK within the limits discussed here and really I'm in no mind to change it.